TY - CONF A1 - John, Sebastian T1 - Sensitivity analysis of residual stresses in composite pressure vessels via modal analysis N2 - Due to high specific stiffness and strength properties, fibre reinforced plastics are used more and more often for the construction of pressure vessels. Within a recent research project run by the Federal Institute for Materials Research and Testing (BAM), aging process of composite pressure vessels is investigated in order to be able to give more accurate lifetime predictions in the future. Focus is set on type III pressure vessels consisting of an aluminium tank which is fully wrapped with carbon fibre reinforced plastics. In order to increase high-cycle fatigue, residual stresses are induced into the pressure vessel during manufacturing process. In particular, residual compressive stresses within the inner aluminium layer have been defined as a main parameter affecting fatigue strength. The aim is to identify and evaluate residual stresses of the pressure vessel by analysing its modal parameters. Through the set-up of a finite-element model potential capability and validity for the use of modal analysis is proven and evaluated, considering influences resulting from manufacturing deviations, too. In the following, a number of stress sensitive modes are defined. Based on these preliminary numerical investigations, a test bench is set up in order to measure pressure vessels via an experimental modal analysis. A final critical evaluation regarding the accuracy of the modal analysis is made by comparing experimental results with data obtained through simulations. T2 - INTER-NOISE 2017 - 46th International Congress and Exposition on Noise Control Engineering CY - Hong Kong, People's Republic of China DA - 27.08.2017 KW - Composite pressure vessel KW - Modal analysis PY - 2017 AN - OPUS4-41843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisermann, René A1 - Basedau, Frank A1 - Kadoke, Daniel A1 - Gründer, Peter A1 - Schoppa, André A1 - Lehr, Christian A1 - Szczepaniak, Mariusz A1 - John, Sebastian A1 - Schukar, Marcus A1 - Munzke, Dorit A1 - Mair, Georg T1 - Distributed strain sensing with sub-centimetre resolution for the characterisation of structural inhomogeneities and material degradation of industrial high-pressure composite cylinders T2 - Proceedings of EWSHM 2018 N2 - Fibre-reinforced plastics (FRP) especially carbon-fibre-reinforced polymer (CFRP) and glass-fibre-reinforced polymer (GFRP) are commonly used materials in high pressure vessels and storage units for automotive and aerospace purposes. Optical fibres are suitable to be integrated or directly applied to the surface of FRP components. Using optical fibres it is possible to monitor the distributed strain profiles and changes within the fatigue life of a pressure vessel to ensure the operational safety. Within artificial ageing experiments we used swept wavelength interferometry (SWI) based distributed strain sensing for the monitoring of commercial high-pressure composite cylinder. This artificial ageing was performed using test conditions of 503bar pressure load (service pressure 300 bar) and 89 °C for 100 h. The polyimide coated optical fibres were glued to the surface externally in circumferential and axial direction. Using distributed strain sensing (DSS) material expansion of over 0.5% were monitored with sub-centimetre spatial resolution. Within the circumferential direction we observed up to 10 % local fluctuation compared to the median strain caused by inhomogeneous material expansion, which could cause local material fatigue. In addition, we determined material degradation manifested itself as localized remaining material expansion and/or contraction. Results have been validated by other non-destructive methods like digital strip projection. T2 - 9th European Workshop on Structural Health Monitoring (EWSHM) CY - Manchester, UK DA - 10.07.2018 KW - Distributed fibre optic sensors KW - Optical backscatter reflectometry KW - Swept wavelength interferometry (SWI) KW - Structural health monitoring (SHM) KW - Composite structures KW - Optical fibre PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-458926 SP - 1 EP - 8 AN - OPUS4-45892 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - John, Sebastian A1 - Mair, Georg A1 - Schoppa, André A1 - Szczepaniak, Mariusz T1 - Monitoring of residual stresses in composite pressure vessels via modal analysis T2 - Proceedings of NOVEM 2018 N2 - Within a current research project at the Federal Institute for Materials Testing and Research (BAM), the degradation process of composite pressure vessels is studied to be able to give more accurate lifetime predictions in future. The presented research is based on type III pressure vessels consisting of an aluminium tank which is fully wrapped with carbon fibre reinforced plastics. Focus is set on the analysis of residual stresses which are induced into the pressure vessel during manufacturing process in order to increase high cycle fatigue. However, with increasing lifetime residual stress conditions do change. To be able to measure and monitor stress conditions, the application of a non-destructive measurement method is aspired. In this paper, potential of an experimental modal analysis is worked out to capture and monitor aging and degradation effects in pressure vessels. With the presented method, information about changes in residual stress can be obtained via an analysis of the modal parameters. To realize an application, first, a finite element simulation is used to prove and evaluate potential capability and validity. In the following, a test bench is set up and successively optimized in its accuracy and efficiency. Sensitivity of the applied measurement technique is experimentally ascertained trough the measurement of several prestress modified pressure vessels. Finally, experimental results are interpreted and evaluated with the help of numerically gained findings. T2 - NOVEM 2018 CY - St. Eulalia, Ibiza, Spain DA - 07.05.2018 KW - Composite pressure vessel KW - Residual stress KW - Modal analysis PY - 2018 VL - 6 SP - Paper 175090, 1 EP - 9 AN - OPUS4-45220 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - John, Sebastian A1 - Mair, Georg A1 - Schoppa, André A1 - Szcepaniak, Marisz T1 - Monitoring of residual stresses in composite pressure vessels via modal analysis N2 - At the Bundesanstalt für Materialforschung und –prüfung (BAM), within a recent research project, the aging process of composite pressure vessels is investigated in order to be able to give more accurate lifetime predictions in future. All investigations are primarily based on type III pressure vessels consisting of an aluminium tank which is fully wrapped with carbon fibre reinforced plastics. Research is focused on residual stresses which are induced into the pressure vessel during manufacturing process in order to increase high cycle fatigue. However, with increasing lifetime residual stress conditions of type III pressure vessels change. For measuring and monitoring inner stress conditions, the application of a non-destructive measurement method is aspired. Within this paper, the potential of an experimental modal analysis is tested to determine aging and degradation effects of pressure vessels. Based on this method, information about changes of the residual stresses can be obtained via an analysis of the modal parameters. Realizing this, first a finite element model is used to prove and evaluate potential capability and validity for the application of an experimental modal analysis. Based on this, a test bench is set up and successively optimized in its accuracy and efficiency. The sensitivity of the applied measurement technique is experimentally evaluated via measuring multiple prestress modified pressure vessels. Furthermore, a selection of prestress modified pressure vessels is monitored via the presented method. Finally, experimentally obtained results are interpreted and evaluated with the help of numerically gained finding. T2 - NOVEM 2018 CY - St. Eulalia, Spain DA - 08.05.2018 KW - Composite pressure vessel KW - Residual stress KW - Cod-age KW - Modal analysis PY - 2018 AN - OPUS4-45242 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - John, Sebastian A1 - Mair, Georg T1 - Sensitivity analysis of residual stresses in composite pressure vessels via modal analysis T2 - Proceedings of the INTER-NOISE 2017; 46th International Congress and Exposition on Noise Control Engineering; Taming Noise and Moving Quiet N2 - Due to high specific stiffness a nd strength properties, fibre reinforced plastics are used more and more often for the construction of pressure vessels. Within a recent research project run by the Federal Institute for Materials Research and Testing (BAM), aging process of composite pressure vessels is investigated in order to be able to give more accurate lifetime predictions in the future. Focus is set on type III pressure vessels consisting of an aluminium tank which is fully wrapped with carbon fibre reinforced plastics. In order to increase high-cycle fatigue, residual stresses are induced into the pressure vessel during manufacturing process. In particular, residual compressive stresses within the inner aluminium layer have been defined as a main parameter affecting fatigue strength. The aim is to identify and evaluate residual stresses of the pressure vessel by analysing its modal parameters. Through the set-up of a finite-element model potential capability and validity for the use of modal analysis is proven and evaluated, considering influences resulting from manufacturing deviations, too. In the following, a number of stress sensitive modes are defined. Based on these preliminary numerical investigations, a test bench is set up in order to measure pressure vessels via an experimental modal analysis. A final critical evaluation regarding the accuracy of the modal analysis is made by comparing experimental results with data obtained through simulations. T2 - INTER-NOISE 2017 46th International Congress and Exposition on Noise Control Engineering CY - Hong Kong, People's Republic of China DA - 27.08.2017 KW - Composite pressure vessel KW - Modal analysis PY - 2017 SP - 6309 EP - 6316 CY - Hong Kong AN - OPUS4-41842 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - John, Sebastian A1 - Duffner, Eric A1 - Mair, Georg T1 - Degradation and damage analysis of composite pressure vessels via experimental modal analysis T2 - NOVEM 2023 Noise and Vibration: Emerging Methods N2 - For mobile gas storage systems, the application of type IV pressure vessels is state of the art. Type IV tanks consist of an inner polymer liner fully wrapped with fibre-reinforced plastic (FRP). Because of the complex fabric of the FRP as well as a difficulty estimable interaction behaviour between the single components under load, there are still no satisfying non-destructive testing methods to assess the current state of failure nor to estimate the level of degradation accurately and economically. At BAM division 3.5, analysing the ageing process of mobile composite pressure vessels is a major task to ensure safe usage over the whole lifetime. In this context, key aspects of our ongoing research activities are the invention of new test procedures and the development of accurate lifetime prediction models. In order to determine the level of degradation or damage, one meaningful non-destructive approach is to analyse the structural dynamic behaviour via an experimental modal analysis (EMA). Over the last few years, different types and sizes of composite pressure vessels have been tested in several research projects. The presented paper gives an insight into how to extract and interpret modal parameters and how to fit them to the results of residual strength tests. T2 - NOVEM Conference 2023 CY - Auckland, New Zealand DA - 09.01.2023 KW - Composite material KW - Pressure vessel KW - Degradation KW - Modal analysis PY - 2023 SP - 57-1 EP - 57-6 AN - OPUS4-58062 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - John, Sebastian A1 - Duffner, Eric A1 - Mair, Georg T1 - Degradation and damage analysis of composite pressure vessels via experimental modal analysis N2 - For mobile gas storage systems, the application of type IV pressure vessels is state of the art. Type IV tanks consist of an inner polymer liner fully wrapped with fibre-reinforced plastic (FRP). Because of the complex fabric of the FRP as well as a difficulty estimable interaction behaviour between the single components under load, there are still no satisfying non-destructive testing methods to assess the current state of failure nor to estimate the level of degradation accurately and economically. At BAM division 3.5, analysing the ageing process of mobile composite pressure vessels is a major task to ensure safe usage over the whole lifetime. In this context, key aspects of our ongoing research activities are the invention of new test procedures and the development of accurate lifetime prediction models. In order to determine the level of degradation or damage, one meaningful non-destructive approach is to analyse the structural dynamic behaviour via an experimental modal analysis (EMA). Over the last few years, different types and sizes of composite pressure vessels have been tested in several research projects. The presented paper gives an insight into how to extract and interpret modal parameters and how to fit them to the results of residual strength tests. T2 - NOVEM 2023 CY - Auckland, New Zealand DA - 09.01.2023 KW - Pressure vessel KW - Composite KW - Modal analysis KW - Degradation PY - 2023 AN - OPUS4-58063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -